[openpgp] public logging of e-mail certificates [was: Re: OpenPGP private certification]

[Daniel Kahn Gillmor <[e-mail]>]

On Wed 2015-04-01 13:38:27 -0400, Phillip Hallam-Baker wrote:
> On Wed, Apr 1, 2015 at 1:22 PM, Daniel Kahn Gillmor
> <[e-mail]> wrote:
>> On Sat 2015-03-28 15:24:38 -0400, Phillip Hallam-Baker wrote:
>>> By that I mean fixed in time. I agree that it does not need to be
>>> public. Only the hash needs to be enrolled.
>>
>> Normal e-mail addresses are low-entropy, right?  this would suggest that
>> they're reversible in most cases without a lot of effort (e.g. consider
>> nsec3-walker, which has similar properties [0]).  how does enrolling
>> only the hash address the privacy considerations effectively?
>>
>>      --dkg
>>
>> [0] http://dnscurve.org/nsec3walker.html
>
> I was planning to enroll the hash of the keysigning which would
> include the signature at minimum.

If you log the hash of the keysigning, then how are the logs useful?
the way that you detect misissuance in a log is that you can scan the
log to see if any new certs have been issued over the identity or
identities that you are interested in monitoring.  If the only thing in
the log is the hash of the full cert, how do you know whether that cert
is one you should be concerned about or not?

           --dkg